Toyota Central R&D Developing Free-Piston Engine Linear Generator
Many years ago I looked at this problem. The hydraulics lab happened to have had a free piston engine dating from 1964. One thing for sure, that device certainly was noisy when running. And just like hydrogen fuel cells - as someone noted here - it will be tomorrows solution. ALWAYS. But it forces you to appreciate rotary motion all the more. However regarding rotating pulsating energy systems, the current practice is to use a crankshaft flywheel and a damper disk to smooth pulsations to a 3-phase generator which of course would prefer a constant torque input delivery. Noting that flywheels and damper disks are large and not inexpensive there must be some way to eliminate both these middlemen ! The mechanically "stiff" flywheel is not sympathetic to pulsating power and despite the use of a damper disk it is the cause of subsequent engine vibration. An idea I suggest is to ...